Electric controller



Feb. 16, 1932. R. EJWEIMER ELECTRIC CONTROLLER Filed March 2o, 1930 .gum

- IIIIIIIIIIIIIIIII l n lvl I I i 1 l l l INVENTOR Patented Feb. 16,1932 UNITED STATES ,PATENT OFFICE ROBERT E. WEIMER, OF COLLIERS, WESTVIRGINIA, ASSIGNOR TO WEIMER-WARREN COMPANY, A CORPORATION F WESTVIRGINIA ELECTRIC CONTROLLER Application led March 20, 1930. Serial No.437,517.

My invention relates to electric controllers and systems for electricmotors.

It is the object of this invention tol provide an improved means forautomatically cutting out resistance from a motor circuit after )o Fig.1 is a vertical section of my improved controller, parts appearing inside elevation. Fig. 2 is a diagrammatic view of a motor system in whichmy controller is incorporated.

On the drawings,1designatesa base or plate of insulating material suchas slate which supports the switch 2 connected thereto by the pivot pin3. The switch has the upstanding member 4 provided at its upper end withthe contact 5 and intermediately of its ends with the armature 6. 7 is afixed contact cooperating with the contact 5 and connected to the base 1by the terminal bolt 8 which extends entirely through the base and issecured thereto by the nut 9 at the back of the base. The nut 10 workson the bolt 8 and clamps the wire 11 between itself and the nut 9.

The electromagnet 12 is secured to the back of the base and has itsmagnetic core extending through to the front of the base where itterminates in the magnetizable head 13 arranged opposite to the armature6 which is spaced from the head when the controller is idle. Oneterminal of the winding 14 of the electromagnet is connected to theterminal bolt 15 which is secured to the base while the other terminalof the winding is secured to the terminal bolt 15 at the back of thebase, the wire or jumper 16 connecting the terminal bolt 15 at the frontof the base to the switch member 4.

17 is a vertical electromagnet having the winding 18 which actuates thecore armature 19 having its upper end provided with the insulated head20. This head is arranged beneath the lateral member 21 of the switch 2so that when the armature 19 is forced up suiiciently far the head byengagement with the member 21 rocks the switch 2 until it assumes theposition shown in dotted lines in Fig. 1 where the contacts 5 and 7 areengaged with each other and the armature 6 is engaged with the head 13.One terminal of the winding 18 is connected to the negative lineterminal 22. The other terminal of the winding 18 is connected by thewire 23 to the bracket 24 attached to the base 1 and having its free end25 provided with the adjustable screw Contact 26 arranged to engage thecontact block 27 on the switch member 4 when the latter is in its openposition as shown in full lines in Fig. 1.

28 is the positive supply line which is connected to the terminal bolt15. 29 is the motor armature which is connected to the line 28 throughthe resistance 30. The shunt field winding 31 of the motor is connectedacross the positive supply line 28 and the negative supply line 32through the winding 14, The connectionbetween the two windings is madeby the wire 33.

rl`he lower end of the armature has the piston 35 working in the barrel34 of a dash-pot, the barrel having a vent 36 opening into the dash-potbarrel below the piston when the latter has travelled upwardly such adistance as to cause the head 20 to approximately reach the switchmember 21.

Current having been supplied to the lines 28 and 32 flows through theresistance 30 and the armature 29. Current also flows from the line 28through the holding winding 14 and field winding 31. The rush of currentthrough the armature starts the motor at a high speed which is reducedas the back E. M. F. builds up. In order to increase the motor speed theresistance 30 is cut out of the armature circuit in a manner now to beexplained.

Current flows initially from the line 28 through the terminal bolt 15,the jumper 16, the switch member 4, the contact block 27, the contact26, the bracket 24, the wire 23, the winding 18 and the terminal 22 tothe negative line 32. The flux generated by current in the winding 18lifts the armature 19 slowly under the control of the dash-pot. After apredetermined interval of timethe piston 35 passes the vent 36 whereuponthe dash-pot control of the armature ceases. The

armature is then very quickly pulled upwardly and engaging the member 21forces the switch 2 from the position shown in Jfull lines to theposition shown in dotted lines in Fig. l. The current just described isopened at the contacts 26 and 27 and the contacts 5 and 7 arepractically simultaneouslyV closed, the switch 2 being held in itsclosed position by the magnetic attraction between the armature 6 andthe magnetized head 13. The opening of the contacts 26 and 27 and theclosing of the contacts 5 and 7 establishes a new circuit, currentflowing therein from the positive line 28 through the'terminal bolt l5,the jumper 16, the switch member 4, the contacts 5 and 7, the wire 11,and the armature-'29 to the negative line 32. The wire 11 joins thearmature circuit at the point 37V which is between the armature 29 andthe resistance 30. VThus, the armature current now short-circuits theresistance 30 causing thev motor to rotate at a higher speed.`

Upon the opening of the contacts 26 and 27 the magnet 17 becomes(le-energized and the armature 19 drops to itsinitial position ready forf another; acceleration operation when theV switch 2 drops open as itwill when the line circuit is open and the holding winding 14 is thereby(le-energized.

I claim: Y 1. In an electric motor system, current supply lines, a motorarmature, a lresistance iniv tially in series therewith, a shunt lieldwinding, an electromagnet, a switch member in its initialposition'connecting the winding of the electromagnet across the linesand in anothervposition closing a shunt around the resistance, anarmature operated by the electromagnet to move the switch member to itssecond position, and a time-limit means for causing the armature tovmove the switch member to its second position after aprede terminedinterval.

2. In an electric motor system, current supl ply lines, amotor armature,a resist-ance initially in series therewith, a shunt Held winding, anelectromagnet,l a switch member in its initial position connectingithewinding. oit' the electromagnetacross the lines and in a circuit inparallel with the resistance and in another position closing a shuntaround the resistance, an armature operated by the electromagnet to movethe switch member to its second position, a'time-limit meansfor causingthe armature to move the switch member toits second position after apredetermined means for electro-magnetically holding the switch memberin its second po- Y sition.

, 3. In anelectricmotor system, current supply llnes, a motor armature,a resistance ini` tially in series therewith, a shunt field wind- Y ing,an electromagnet, afswitch member in Aits initial position connectingthe winding of the electromagnet across the lines and in

